Historically, documents were printed on paper or other non-modifiable, non-interactive media, and did not allow any user modification of the information, or, for example, of relationships between data points. Moreover, documents could not be updated when new information appeared, and the concept of “databases” in the modern sense of this word did not even exist, rendering the concept of updating them moot.
Prior to the computer age, there were essentially two forms of recourse whenever a map needed modification: 1) to enter a correction by hand on the paper copy or copies of the map; or 2) to reprint the map with the correction made on the original. Manual corrections are time-intensive; particularly for multiple modifications, and by definition do not update any of the other remaining copies of the map. The second option of reprinting the map is expensive, and is also an impractical way to respond to frequent modifications.
In the current age, paper maps have been largely superceded by databases, documents, and maps in digital, electronic formats, capable of being updated as desired and able to respond to a selected range and type of operator input and to produce operator-requested output. Many electronic documents and electronic databases in common usage today comprise information related to geographic location(s). Indeed, it is not easy to think of a class of electronic documents or a class of electronic databases that does not at least occasionally incorporate some form of geographically related information.
Examples of electronic databases that is relevant to certain embodiments of the present invention are “geospatial databases”, commonly referred to as “electronic maps” or “digital maps”. Today, maps have evolved well beyond their centuries-old status as static paper depictions of a non-adjustable data set as recorded at one particular time. For simplicity, much of the discussion below refers to electronic maps, although the points made also apply to electronic documents and electronic databases, other than maps, that contain geographic information.
One of the benefits of a digital map over a traditional paper-based map is its inherent flexibility and its ability to portray large amounts of data. Paper maps are necessarily limited in the amount and type of information they can portray, within the constraints of their physical formats. Paper maps are also difficult to update.
Digital maps do not suffer from these problems. While earlier digital maps may have seemed merely like a scanned version of the paper product, today's modern digital maps are much more powerful. Information can be included in the map and either displayed, or not displayed, depending on the wishes of the operator.
Today's digital maps, also known as electronic maps, can allow for regular modification of data points included in the map, in addition to active operator selection of desired geographic features of interest. As new information arises, of a type specifically relevant to a map of interest, the whole map can be quickly updated to reflect changes or corrections to all or just a small subset of locations.
Digital maps may be capable of responding to certain types of operator input and may be capable of offering a range of operator-adjustable output. Current electronic maps may offer the operator the option to select the scale at which the map is viewed. Often this is done using a “zoom-in” and/or “zoom-out” capability. This feature, while important and useful, does not actually change the content contained in a particular map, but rather re-presents the map at a different level of detail and with a different geographic focus.
A typical application of electronic maps is in the travel industry, whereby digital maps are used to quickly and automatically chart travel routes and to locate destinations. Digital maps have found a particularly common everyday use in automobiles, wherein Global Positioning Systems (GPS) and other position determination devices are used in association with a digital map to automatically track the position of a car and display the position on a map, for example, to guide the driver to a particular destination.
Digital maps are often also used in commercial environments, for example, in calculating optimized routes for delivery drivers to take when performing deliveries, or for providing accurate directions for emergency and medical crews to follow when responding to emergency calls. For many years, the electronic map industry has also supplied maps to the military for use in military applications. Digital maps find a use in all aspects of industry, including for ground-based, maritime, and aviation purposes. As people have become more familiar with portable, handheld electronic devices such as Personal Digital Assistants (PDA's) and smart phones, which are increasingly distributed together with electronic maps stored therein, the electronic or digital map industry has grown to infiltrate virtually every aspect of society.
Some currently available digital maps allow for linking between a text address and its location on the map. If, for example, an operator inputs a street address into the Yahoo! Maps software application, MapQuest, or a similar Internet mapping website, the output indicates the location of that particular address on a map that is drawn of the surrounding area. Essentially a map of the region encompassing the address of interest is constructed around the selected point. The map may contain overlays of useful information. For example, a street map of San Francisco may be overlaid with a map of the railroad system in San Francisco and that map in turn overlaid by icons representing San Francisco restaurants and parking facilities.
However, these various overlays are “map-level overlays”, meaning that they are registered one to another on the basis of their coordinates. No interactivity is typically available between different points in the overlay or between a point in one overlay and a point in another overlay. While such a coordinate overlay may result in something that appears to an end-user like a single map, it cannot dynamically function like one fully integrated, intelligent digital map. In a sense, the entities in one layer know nothing about the entities in any other layer and hence cannot support further data processing related to useful linkages between those entities. Moreover, such an overlay map is only possible if it is permitted by the scales, formats and coordinate systems of the different maps and different spatial data files. Such an overlay map is not feasible if the information in one or more documents is not presented in the form of a map.
For example, the restaurant information may take the form of a text list of restaurant names and addresses. In this case, using traditional methods there is no easy way to seamlessly integrate the restaurant data with the railroad and street data of our example. Solutions in the past simply found the coordinates of the restaurant by finding its address located within the street map and generating a set of icons to display as an overlay. While this allowed for a simple address linkage it was incapable of any more sophisticated linkages.
Alternatively, a richer set of linkages could be made possible, but only if all information has been comprised within the same single integrated map file. This puts the increasingly untenable burden on a single map vendor to integrate the entire body of spatial knowledge into a single electronic map. However, in most situations, the map vendor doesn't even have access to all the necessary information, so despite their best intentions, it is increasingly difficult to create a completely integrated map.
Finally, in accordance with traditional methods, any changes in the placement of an entity on one layer cannot automatically be coordinated with entities in other layers, thereby requiring much extra work in keeping all of the layers integrated.
With the progression of the Internet and generally, the information age, increasingly more data with spatial components is becoming available, that could be linked together in an integrated intelligent electronic map. It is a shortcoming of the traditional methods that the layered approach will not handle such intelligent linkages, and hence will limit the ability to query the full richness of the spatial content becoming available. Also, because of the intensive labor in keeping the coordinate-related data synchronized, the traditional techniques limit the overall amount of data that can be maintained and updated. Moreover, given the explosion of spatially related information that is digitally available and of interest to map users it is neither economically nor logistically feasible for map-related enterprises to create and maintain the entire universe of such information. It is these, and other limitations of the prior art that the present invention is designed to address.